2 pounds sirloin tips, cubed
1/2 yellow onion, chopped
2 (10.75 ounces) cans condensed cream of mushroom soup
1 cup milk
1/2 cup red wine
1 (1.25 ounce) package beef with onion soup mix
2 (16 ounce) packages egg noodles
Heat a large skillet over medium-high heat (or slow cooker). Saute beef sirloin tips with onion in the hot skillet until beef is browned, about 5 minutes.
Stir cream of mushroom soup, milk, red wine, and beef with onion soup mix together in a bowl, pour into the skillet, and stir to coat beef in the soup mixture; bring to a simmer, reduce heat to low, place a cover on the skillet, and cook until the beef tips are tender about 2 hours.
Reduce heat to the lowest setting and continue cooking until the beef pulls apart easily with a fork, at least 4 hours more.
Bring a large pot of lightly salted water to a boil. Cook egg noodles in the boiling water, stirring occasionally until cooked through but firm to the bite, about 5 minutes. Drain.
Ladle beef tips mixture over egg noodles.